Lock



Nov..9 19.26.

` A. LAWRENCE LOCK`v Filed August 22, `l923 Patented Nov. 1926,

ALFRED LAWRENCE, OF S'I'AMFORD, CONNECTICU'I', A SSIGNOVB, TO THE YAE & 'I'OW'NE MANUFACTURING COMPANY, OF STAMFOBID, CONNECTICUT.

LOCK.

Application filed. Augnst 22,il923., l Serial No. 658,803.

This invention relates to improvements in looks and more particularly to such as door looks. em'ployingI stop-work or dead-lockmg,` means for the latch bolt. l Looks of this type are often used on doors for public entrances or as night latches and it sometimes becomes desirable to have 'the bolt held in its inactive position during` the day time. p v

An Object of my present invention is to provide mea-ns, without complicating Vthe 4 mechanism With additional parts, Whereby the stop plunger in Cooperation with a part lon the knob spindle7 (the outside roll-back on' the knob spindle, for example) shall 'be operable to prevent return rotation when the latch bolt shall have been retracted and hence causethe latch bolt to be retained in retracted position.

The accompanying drawing illustrates a look mechanism in which my improvements are embodied.

In the drawing, ,I have shown my 'improvements in a mortise look of the type disclosed in patent to Reinhold Schoell January 9, 1917, No. 1,212,117, but it will be understood that my improvements are applicable to any look of this general type in f which stop-work is employed.

VsoV

In the look structure shown in the drawing, the lever 1 is pivoted to the lock casing and is norlnally held by a spring 2, in postion to be engaged by the cam 3 actuated by the knob spindle 4 and the outside rollback which is indicated at 5. The lever l Vis provided with a laterally projeoting pin 6 adapted to engage lthe dead-looking` lever l 7 at the rear of its pivot 8, so that when the lever'l is moved by either the key or knob inechanism, the pin 6 engaging the lever 7 will elevate the rear end and depress the front end of said lever and remove the front end from the path of travel of the bolt and permit the latter to be' retracted.

The lever 1 rests in front of the cross-bar 9 at the rear end of the tail 10 of the bolt 11, hence when moved rearwardly either by the key or knob mechanism it Will retract the bolt, which is normally projected bythe spring 12.

As is common in looks of the type to which my improvement relates, stop-work is provided to V latch bolt by manlpulation of the knob or to permit such operation. `This stop-work inrevent operation -of the cludes a manually -operable stop-plunger 13" which is cooperable With the roll-back When this plunger is inoved out of operative relation to the roll-back, the mechanism may' shifted outwardly, the knob spindle will be l free to turn, and if it be turned to retract Vthe bolt, the shoulder lt of the roll-back will' be disposed in the path of movement of the inner end portion of the stop-plunger 13'. By now pressing the stop-plunger 13 in- ,wardly, the Vinner end portion thereof will become engaged with the shoulder llk'of thev roll-'back 5, preyenting return movement ofV the latter-and thus retaining the latch bolt in its retracted position, inasmuch as they lever 1 bearingagainst the cross-bar 19 Will be held in the retracted position by the rollo back and the co-acting cam 3.

Having fully described my invention what I claim as new and desire to s'ecure by Letters-Patent, is: V

In a lock, the combination' of a bolt7 a levero, pivoted below the bolt and engaged therewith to retract the same, a-knob spindle, a roll-back carried by the spindle and operable to rock the lever and effect retraction of the bolt, the roll-back ,being provided in its edge with aV centralnotch and with shoulder spaced from the notch, and a stop plunger slidable to and from the rollback v to engage the notch and prevent rocking;I of the spindle or to engage the shoulder and hold the bolt retracted.

In 'testimony whereof, I have signed this 

